Express your answer as a mixed number simplified to lowest terms. $15\dfrac{1}{20}+7\dfrac{1}{5} = {?}$
Explanation: Separate the whole numbers from the fractional parts: $= {15} + {\dfrac{1}{20}} + {7} + {\dfrac{1}{5}}$ Bring the whole numbers together and the fractions together: $= {15} + {7} + {\dfrac{1}{20}} + {\dfrac{1}{5}}$ Add the whole numbers: $=22 + {\dfrac{1}{20}} + {\dfrac{1}{5}}$ Find a common denominator for the fractions: $= 22+\dfrac{1}{20}+\dfrac{4}{20}$ Add the fractions: $= 22+\dfrac{5}{20}$ Combine the whole and fractional parts into a mixed number: $= 22\dfrac{5}{20}$ Simplify to lowest terms: $= 22\dfrac{1}{4}$